What is the goal of the model and is the training data relevant to that?
Model means you can say a Prototype we make regarding to our task.
As we first train our model on some observed or you can say bench-marked data ; called as TRaining phase of model.

Then we apply that model to our problem (test data) you can say in order to evaluate how  much well you have trained your model.
Training data we use related to our task or use bench marked data for any model of AI.
hope you find this answer useful .